black smoke

[mealexme]

I have noticed, only when cold, and only when revving (I rev to make sure its smooth before I pull away so I dont stall it) that the bike emits black smoke aswell as white. I know the white is just water vapor and the black is something possibly to be worried about. I know it is usually oil being burnt.

But it only happens when cold, and only at high revs. Is that something a bike would do if the seals have gone or is it possible its just unburnt petrol or something?

Revving the bike does not emit the black smoke after about a minute of the engine being on, even if there is still white smoke coming from it.

It does not emit blue smoke either and the black is only a very small amount.

When the bike is started warm, or has been running for more than a minute this doesnt happen at all.

If it is the seals, I heard briefly about a product that you can add to the oil to make the seals expand, or something. Anyone know about this? And if there is nothing wrong with the seals, is there any harm in using it anyway? The bike is 8 and a half yo

[Colin the Bear]

High revs when cold is a no no. Let it warm up before using high revs.

[megawatt]

Usually it's the valve guide seals that need replacing. Black smoke from an engine is serious! If it keeps doing it , fix it. Never heard of the oil additive.

[Fozzie]

Is your bike carbed?

If so and if only doing it under revs it is probably just running rich.

Blue/grey smoke is oil burning and it stinks.

If you have had your choke on or it is still on you are choking the air supply and burning to much petrol and hence. Little bit of black smoke.

If it does it at running temp then you have an issue as megawatt suggested

[mealexme]

Is your bike carbed?

If so and if only doing it under revs it is probably just running rich.

Blue/grey smoke is oil burning and it stinks.

If you have had your choke on or it is still on you are choking the air supply and burning to much petrol and hence. Little bit of black smoke.

If it does it at running temp then you have an issue as megawatt suggested

thats the sort of answer I was hoping for haha.

It is carbed and only does it on choke. It is definately black rather than blue/grey

And I know revving is bad for the engine when cold, I only do it to make sure it has warmed up and isnt going to stall when I pull away as I do it at an angle and am likely to drop it. Turns out, sometimes its not warmed up (On those really cold mornings)

I will keep an eye on the exhaust, and oil levels though, just encase

[Mrbarry]

You can rev a cold engine, just not to high revs. 1500-2000 is ok. And yes black smoke is fuel burning, less choke would help but if its only for 30 seconds on start up its bit a huge deal.

White smoke is water, if it stops after a few minutes its ok, if not its water entering the bores, normaly a head gasket issue, can be warped or cracked block or head etc too.

Blue smoke is oil. Not good at all if just at cold start it is commonly valve steam seals, if at all times normaly rings or ring lands have gone. Can also be head gasket or warpage related.

[eastanglianbiker]

You can rev a cold engine, just not to high revs. 1500-2000 is ok. And yes black smoke is fuel burning, less choke would help but if its only for 30 seconds on start up its bit a huge deal.

White smoke is water, if it stops after a few minutes its ok, if not its water entering the bores, normaly a head gasket issue, can be warped or cracked block or head etc too.

Blue smoke is oil. Not good at all if just at cold start it is commonly valve steam seals, if at all times normaly rings or ring lands have gone. Can also be head gasket or warpage related.

op hasnt got to worry about water entering the bores as the bike is oil cooled and he never washes it

[Mrbarry]

Lol furry muff

[mealexme]

You can rev a cold engine, just not to high revs. 1500-2000 is ok. And yes black smoke is fuel burning, less choke would help but if its only for 30 seconds on start up its bit a huge deal.

White smoke is water, if it stops after a few minutes its ok, if not its water entering the bores, normaly a head gasket issue, can be warped or cracked block or head etc too.

Blue smoke is oil. Not good at all if just at cold start it is commonly valve steam seals, if at all times normaly rings or ring lands have gone. Can also be head gasket or warpage related.

op hasnt got to worry about water entering the bores as the bike is oil cooled and he never washes it

Took me two days to wash the thing, looks sparkling.

Washed, dried, put bumper care on all the black plastics to make them shine, cleaned the undertray, rear hugger, polished the undertray, even gave the rear spring and bits and peices in front of the hugger that you cant get your hand into. Polished the chrome looking clocks which are a pain to get to, polished the exhaust etc etc etc. I even painted all the tiny chips in the paintwork as well as cleaned the brakes, cleaned and lubed the chain. Really does look like new. All set for the 400 mile ride tomorrow to get it all dirty again... sigh

And yea, the white smoke stops after a while. Am 100% sure its only water vapor.

Thanking you guys!

[Colin the Bear]

The white smoke is probably condensation burning off.

The black smoke is money wafting down the street ie unburned fuel. It hasn't done a job of any kind apart from maybe fouling the plugs and coking the head.

An engine is it's at its most vulnerable when cold. The lubricant is sat in the sump and isn't at working temperature so it's at its least effective.

Precision parts haven't expanded to their working size, so consequently bearings may be dry and tight.

Using high revs to warm the engine will increase engine wear and not speed dissipation of heat by much.

The first part of the choke raises tick over speed. Once you've started the motor, let the bike sit on fast tick over for a few minutes, typically while you helmet and glove up.

An extra 90 seconds on your cold start routine will add many tens of thousands of miles to the life of the engine.

[mealexme]

The white smoke is probably condensation burning off.

The black smoke is money wafting down the street ie unburned fuel. It hasn't done a job of any kind apart from maybe fouling the plugs and coking the head.

An engine is it's at its most vulnerable when cold. The lubricant is sat in the sump and isn't at working temperature so it's at its least effective.

Precision parts haven't expanded to their working size, so consequently bearings may be dry and tight.

Using high revs to warm the engine will increase engine wear and not speed dissipation of heat by much.

The first part of the choke raises tick over speed. Once you've started the motor, let the bike sit on fast tick over for a few minutes, typically while you helmet and glove up.

An extra 90 seconds on your cold start routine will add many tens of thousands of miles to the life of the engine.

 

Thanks for the input COB. I do usually start the bike, then turn on the heated grips (if its really cold) , check my phone, turn the bluetooth on on the helmet and phone, connect them up and choose some music and then don my gear. obviously thats not long enough though on the really cold days.

Its not like it happens every day, its only done it about 3 or four times since I have had it.

[mealexme]

The white smoke is probably condensation burning off.

The black smoke is money wafting down the street ie unburned fuel. It hasn't done a job of any kind apart from maybe fouling the plugs and coking the head.

An engine is it's at its most vulnerable when cold. The lubricant is sat in the sump and isn't at working temperature so it's at its least effective.

Precision parts haven't expanded to their working size, so consequently bearings may be dry and tight.

Using high revs to warm the engine will increase engine wear and not speed dissipation of heat by much.

The first part of the choke raises tick over speed. Once you've started the motor, let the bike sit on fast tick over for a few minutes, typically while you helmet and glove up.

An extra 90 seconds on your cold start routine will add many tens of thousands of miles to the life of the engine.

 

Thanks for the input COB. I do usually start the bike, then turn on the heated grips (if its really cold) , check my phone, turn the bluetooth on on the helmet and phone, connect them up and choose some music and then don my gear. obviously thats not long enough though on the really cold days.

Its not like it happens every day, its only done it about 3 or four times since I have had it.

[Fozzie]

When I start my bike, most instances will see me leave it to run for a minute or two while I unlock the chain on its wheel, then put my bag, gloves and helmet on and make sure everythings good to go.

If you need to make a quick getaway try to only do 30 seconds then very gently set off and only use a few thousand revs on a 600. I do this then I have to stop for a traffic light at the bottom of my road so it gets a good minute of warming up then.

Revving it to 4000 wont do harm, my bike automatically fast idles to 3000rpm. Honda do it to get it to warm up quicker.

[Adam]

When I start mine up it revs to about 4000rpm then slowly drops, but I let it warm up for about 5 mins before riding off. I do the same as Fozzie start the bike and get myself ready, lets the engine and oils warm up.